ELIMINATION OF TOXIC ELEMENTS BY NATURAL AND SYNTHETIC ADSORBENTS

The adsorption of Zn(II) and Cu(II) onto siderite (S) and kaolin (K) and adsorption of As(V) ontobentonite (B) was studied. The chemical modification – precipitation of MnO2 on the kaolin (KM) andsiderite (SM) surface was used to improve the adsorption properties of natural materials for theirapplication in columns. In the batch tests the higher adsorption capacity was observed for the KMsample. The binary solution of Zn(II)/Cu(II) was percolated through the columns filled with quartz sand(QS) as a bearer of KM or SM. The effect of toxic elements removal reached in average 90 % for bothcolumns.The adsorption of As(V) onto natural bentonite (B) and synthetic magnetic particles (MP) was studiedby batch as well as column tests. Whereas the B sample did not perform good adsorption properties inbatch test, in dynamic conditions its effect was comparable with MP. The effect of As(V) removal wasstudied in a number of series with different materials beddings and cycles repetitions. The resultsshowed that the most effective was the column filled with QS+B+MP containing more coarse-grainedfraction of bentonite. In the second cycle its removal effect reached 60 % of As(V) elimination from thesolution.

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Effects of Calcination Temperature and Chemical Modification on the Adsorption of Cd and As(V) by Biochar Derived from Pteris Vittata

10.21203/rs.3.rs-287389/v1 ◽

2021 ◽

Author(s):

Kazuki Sugawara ◽

Kouhei Ichio ◽

Yumiko Ichikawa ◽

Hitoshi Ogawa ◽

Seiichi Suzuki

Keyword(s):

Chemical Modification ◽

Adsorption Capacity ◽

Toxic Elements ◽

Plant Biomass ◽

Pteris Vittata ◽

Adsorption Capacities ◽

Biomass Resources ◽

As Adsorption ◽

Effective Use ◽

Very High

Abstract Phytoremediation can be applied successfully to solve the serious worldwide issue of arsenic (As) and cadmium (Cd) pollution. However, the treatment of biomass containing toxic elements after remediation is a challenge. In this study, we investigated the effective use of biomass resources by converting the As hyperaccumulator P. vittata into biochar to adsorb toxic elements. Plant biomass containing As was calcined at 600 °C, 800 °C, and 1200 °C and its surface structure and adsorption performances for As and Cd were evaluated. Calcination at 1200 °C increased the specific surface area of the biochar, but it did not significantly affect its adsorption capacity for toxic elements. The calcined biochar had very high adsorption capacities of 90% and 95% for As and Cd, respectively, adsorbing 450 mg/g-biochar of both elements. The As adsorption rate was improved by FeCl3 treatment. However, the adsorption capacity for Cd was not significantly affected by the NaOH treatment. In conclusion, it was found that after phytoremediation using P. vittata biomass, it can be effectively used as an environmental purification material by conversion to biochar. Furthermore, chemical modification with FeCl3 improves the biochar’s adsorption performance.

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Heavy metal adsorption capacity of powdered Chlorella vulgaris biosorbent: effect of chemical modification and growth media

Environmental Science and Pollution Research ◽

10.1007/s11356-021-12396-w ◽

2021 ◽

Author(s):

Gwonho Joo ◽

Wooram Lee ◽

Yongju Choi

Keyword(s):

Heavy Metal ◽

Chemical Modification ◽

Adsorption Capacity ◽

Chlorella Vulgaris ◽

Metal Adsorption ◽

Growth Media ◽

Heavy Metal Adsorption

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Morphology dependent adsorption of methylene blue on trititanate nanoplates and nanotubes prepared by the hydrothermal treatment of TiO2

Water Science & Technology ◽

10.2166/wst.2016.519 ◽

2016 ◽

Vol 75 (2) ◽

pp. 350-357

Author(s):

Graham Dawson ◽

Wei Chen ◽

Luhua Lu ◽

Kai Dai

Keyword(s):

Methylene Blue ◽

Adsorption Capacity ◽

Surface Area ◽

Pore Volume ◽

Hydrothermal Reaction ◽

Low Cost ◽

High Surface ◽

High Surface Area ◽

High Capacity ◽

Adsorption Properties

The adsorption properties of two nanomorphologies of trititanate, nanotubes (TiNT) and plates (TiNP), prepared by the hydrothermal reaction of concentrated NaOH with different phases of TiO2, were examined. It was found that the capacity for both morphologies towards methylene blue (MB), an ideal pollutant, was extremely high, with the TiNP having a capacity of 130 mg/g, higher than the TiNT, whose capacity was 120 mg/g at 10 mg/L MB concentration. At capacity, the well-dispersed powders deposit on the floor of the reaction vessel. The two morphologies had very different structural and adsorption properties. TiNT with high surface area and pore volume exhibited exothermic monolayer adsorption of MB. TiNP with low surface area and pore volume yielded a higher adsorption capacity through endothermic multilayer adsorption governed by pore diffusion. TiNP exhibited a higher negative surface charge of −23 mV, compared to −12 mV for TiNT. The adsorption process appears to be an electrostatic interaction, with the cationic dye attracted more strongly to the nanoplates, resulting in a higher adsorption capacity and different adsorption modes. We believe this simple, low cost production of high capacity nanostructured adsorbent material has potential uses in wastewater treatment.

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Preparation of crosslinked chitosan magnetic membrane for cations sorption from aqueous solution

Water Science & Technology ◽

10.2166/wst.2017.078 ◽

2017 ◽

Vol 75 (9) ◽

pp. 2034-2046 ◽

Cited By ~ 9

Author(s):

Adnan Khan ◽

Samina Begum ◽

Nauman Ali ◽

Sabir Khan ◽

Sajjad Hussain ◽

...

Keyword(s):

Experimental Data ◽

Aqueous Solution ◽

Adsorption Capacity ◽

Magnetic Particles ◽

Isotherm Models ◽

Chitosan Membrane ◽

Dilute Aqueous Solution ◽

Chitosan Membranes ◽

The Fourier Transform ◽

Time Required

A chitosan magnetic membrane was prepared in order to confer magnetic properties to the membrane, which could be used for the removal of cations from aqueous solution. The crosslinked magnetic membrane was compared with pristine chitosan membrane in term of stability, morphology and cation adsorption capacity. The fabricated magnetic materials are thermally stable as shown by thermogravimetric curves. The membrane containing nickel magnetic particles (CHNiF-G) shows high thermal stability compared to the other membranes. The Fourier transform infrared spectroscopy showed successful preparation of chitosan magnetic membrane. Scanning electron microscopy micrographs showed the rough surface of the membrane with increased porosity. The prepared chitosan membranes were applied to cations of copper, nickel and lead in dilute aqueous solution. The chitosan membrane showed the following adsorption order for metallic cations: Cu2+ > Ni2+ > Pb2+, while CHNiF-G showed higher capacity, 3.51 mmol g−1 for copper, reflecting the improvement in adsorption capacity, since the amount of copper on pristine chitosan gave 1.40 mmol g−1. The time required for adsorption to reach to the equilibrium was 6 h for the selected cations using different chitosan membranes. The kinetic study showed that adsorption followed pseudo-second order kinetics. The most commonly used isotherm models, Freundlich, Langmuir and Temkin, were applied to experimental data using linear regression technique. However, The Temkin model fits better to experimental data.

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Synthesis and characterization of thiol-polystyrene microsphere and its adsorption properties of thallium

E3S Web of Conferences ◽

10.1051/e3sconf/202123701001 ◽

2021 ◽

Vol 237 ◽

pp. 01001

Author(s):

Youze Xu ◽

Yuehui Chen ◽

Yuanyuan Zhao ◽

Shuang Zhou ◽

Guangyi Fu ◽

...

Keyword(s):

Adsorption Capacity ◽

Raw Materials ◽

Removal Rate ◽

Adsorption Properties ◽

Membrane Diffusion ◽

Polystyrene Microspheres ◽

Polystyrene Microsphere ◽

Control Step ◽

Ft Ir ◽

Modified Polystyrene

Thallium (Tl) is highly toxic in the environment. In order to solve the harm of Tl pollution to the environment, thiol-polystyrene microsphere (TPM) with good adsorption properties for Tl were prepared in this paper. The GAUSSIAN software was used to calculate the adsorption performance of the TPM on Tl+, and the adsorption mechanism was discussed. The thermogravimetric analysis show that the TPM prepared with chloromethyl polystyrene microspheres (CPM) and thiourea as the main raw materials has good chemical thermal stability. In the Tl+ solution of 1mg/L, the adsorption and removal rate of the TPMs in was 99%, with a significant adsorption of Tl+ properties. When the dosage of TPM is 0.4L/g, pH is 6-10, temperature is 5-20 °C, and adsorption time reaches 640min, thallium-containing water with Tl+ concentration of 5mg/L can be treated to within the national discharge standard (5μg/L). The analytical effect of 0.5mol/L dilute sulfuric acid on TPM can reach 99.96%, and the adsorption capacity of TPM on Tl+ is reduced by only 0.1% after repeated use 4 times, which has good regeneration performance. The modified polystyrene microspheres were characterized by EDS, FT-IR, Raman spectra and XPS, and it was proved that the TPM were ligated with Tl+ through the grafted mercapto group, so as to adsorb and remove Tl+ from the solution. According to the isotherm and kinetic model of TPM adsorption Tl+, the maximum saturated adsorption amount of TPM to Tl+ can reach 3.47mg/g, mainly chemical adsorption, and the membrane diffusion stage is the main control step of TPM adsorption Tl+. The results showed that the TPM could be a promising adsorbent with good adsorption capacity and reusability for Tl+ removal from wastewater

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Влияние азотного допирования и механического напряжения на адсорбционную способность графдиена

Физика твердого тела ◽

10.21883/ftt.2019.02.47144.215 ◽

2019 ◽

Vol 61 (2) ◽

pp. 405

Author(s):

И.Ю. Долинский ◽

К.С. Гришаков ◽

В.С. Прудковский

Keyword(s):

Mechanical Stress ◽

Adsorption Capacity ◽

Atomic Hydrogen ◽

Quantum Chemical ◽

Adsorption Properties ◽

Quantum Chemical Simulation ◽

Nitrogen Doped ◽

Chemical Simulation ◽

Mechanical Stretching

AbstractThe quantum chemical simulation of adsorption of atomic hydrogen on pristine and nitrogen-doped graphdienes has been performed. The preferential sites, adsorption on which is most energetically beneficial, are indicated. The nitrogen presence is shown to substantially increase the adsorption capacity of the sheet. A capacity of the nitrogen-doped graphdiene to be reversibly stretched by 4% under action of external mechanical stress is demonstrated. A mechanical stretching is found to enable the control of the adsorption properties of pristine and also doped graphdienes.

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Synthesis and Characterization of Highly Efficient Oil-Water Separation, Recyclable, Magnetic Particles CoFe2O4/SDB

10.21203/rs.3.rs-601296/v1 ◽

2021 ◽

Author(s):

Cailin Liu ◽

Li Yu ◽

Yue Fan ◽

Chang Li ◽

Xianyan Ren ◽

...

Keyword(s):

Adsorption Capacity ◽

Magnetic Particles ◽

In Situ Polymerization ◽

Solid Phase ◽

Sol Gel ◽

Water Separation ◽

Practical Applications ◽

Oil Water Separation ◽

Oil Water

Abstract In the oil-water separation, the difficulty to recover and low hydrophobicity are key limitation factors for practical applications. In this paper, we design Cobalt ferrite hybird Polystyrene divinylbenzene microspheres (CoFe2O4/SDB), which were conducted through in-situ suspension copolymerization. The CoFe2O4 is prepared by low heat solid phase sol-gel method. It had been found that the CoFe2O4/SDB have a spherical structure, good adsorption behavior, highly hydrophobicity and even superhydrophobicity. The adsorption capacity of CoFe2O4/SDB composites could absorb kerosene up to 6 times of its own weight. Interestingly, kerosene can be easily separated from the surface of CoFe2O4/SDB particles with ultrasonic operation. CoFe2O4/SDB particles can still maintain good hydrophobicity and adsorption capacity of kerosene after 11 cycles after drying. With in situ polymerization of St、DVB and CoFe2O4, CoFe2O4/SDB as a promising absorbent of kerosene which has great potential in application of oil-water separation.

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Effect of Heat Modification and Biofilm on Zeolite Adsorption Properties

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.439-440.956 ◽

2010 ◽

Vol 439-440 ◽

pp. 956-959 ◽

Cited By ~ 1

Author(s):

Hong Long ◽

Jin Long Zuo

Keyword(s):

Ion Exchange ◽

Adsorption Capacity ◽

Mean Value ◽

Adsorption Properties ◽

Ammonia Removal ◽

Ammonium Ion ◽

Modified Zeolite ◽

Langmuir Isotherms ◽

Bench Scale ◽

And Diffusion

In order to improve ammonia removal capability from wastewater, zeolite was modified with heat and biofilm in this paper. The results showed that the adsorption capacity of heat modified zeolite could be reach mean value of 120.18meq/100g, which was 1.55 times than virgin zeolite. The results of bench scale experiments also showed that the data in the experiments were in line with Langmuir isotherms for ammonium ion absorbed onto heat modified zeolite. Moreover the biofilm which attached on the surface of heat modified zeolite only modified the surface feature of modified zeolite, while ion-exchange and diffusion procedure were not affected.

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Preparation and Adsorption Properties of Starch-g-Polyacrylamide/Montmorillonite Nanocomposites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1120-1121.343 ◽

2015 ◽

Vol 1120-1121 ◽

pp. 343-346

Author(s):

Cai Ning Zhang ◽

Xu Man Wang

Keyword(s):

Aqueous Solution ◽

Methylene Blue ◽

Adsorption Capacity ◽

Crosslinking Agent ◽

Adsorption Properties ◽

Experimental Results ◽

Solution Polymerization ◽

Preparation Conditions ◽

Montmorillonite Nanocomposites

By means of solution polymerization, a series of cross-linked starch-g-polyacrylamide/ montmorillonite (St-g-PAM/MMT) nanocomposites were prepared and used to adsorb methylene blue (MB). The effects of different preparation conditions on the adsorption capacity of the nanocomposites were investigated. The experimental results demonstrated that the prepared St-g-PAM/MMT nanocomposites were effective adsorbents for removal of MB from aqueous solution. Furthermore, adsorption capacity increased with the MMT contents up to 14% and decreased as the MMT contents further increased. Adsorption capacity increased with the increasing of the ratio of starch to acrylamide, whereas adsorption capacity decreased with the increasing of crosslinking agent contents.

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